1. Field of the Invention
The present invention relates to a tying band cluster to be loaded in an automatic bundling machine for wiring harnesses.
2. Prior Art
FIG. 8 shows a conventional tying band cluster. The tying band cluster 15 is formed of synthetic resin and has a number of tying bands 20 connected in series. Each band consists of a band body 17 with engagement grooves 16 and a head portion 19 with an engagement hole 18, the band body and the head portion formed as one piece. The tying band 20 has the end of its head portion 19 fused with the end 17a' of a band body 17' of the next tying band 20'. In this way, a number of tying bands are connected longitudinally in series to form a typing band cluster 15.
The individual tying band 20' is formed in one piece by molding dies 21, 21, from the head portion 19' to the end 17a' of the band body 17'. During the molding process, the end of the band body 17' is fused, as indicated by an arrow T, with the end of the head portion 19 of the tying band 20 that was formed previously. In the drawing, denoted 22 is a gate, which is preferably set at the base portion 17b' of the band body 17' which requires a large strength. A direction U represents the direction of feed. Designated 23 is a fixing clip.
During the process of making the above-mentioned tying band cluster 15, however, the head portion 19 of the typing band 20 that was previously formed is already cool when the next band is molded, so that the end 17a' of the band body 17 ' of the next tying band 20' does not easily fuse with the head portion 19 of the previously formed band 20. Hence, when the band cluster 15 is loaded and used in the automatic bundling machine, a connecting portion c may easily get disconnected, bringing the bundling work to a halt.
FIG. 9 shows a tying band cluster disclosed in the Japanese Utility Model Preliminary Publication No. Heisei 1-128566.
The tying band cluster 24 consists of a plurality of parallelly arranged tying bands 25 with their head portions 26 formed continuous with a connecting strip 27. With this construction, connecting portions 29 between the band bodies 28 and the connecting strip 27 are positioned close to the gate (not shown), so that the strength of the connecting portions 29 can be increased.
The tying band cluster 24, however, has a drawback that the connecting strip 27 requires an extra amount of synthetic resin material, raising the cost.